The objectives of the proposed investigation are: 1) to obtain more information about lectin structure by studying such parameters as valence, differences and interactions between various molecular forms of a lectin, subunit association, and analysis of products produced by fragmentation and chemical modification; 2) to use such information in attempts to produce an active, homogeneous, monovalent form of a lectin and 3) to learn more about the natural role of lectins by following the development and distribution of a lectin during the life cycle of a plant. The Dolichos biflorus and Triticum vulgaris (wheat germ) lectins will be the principal lectins under investigation although this work may be extended to other lectins. Such information should enhance the flexibility and adaptation of these lectins for use in studies of complex carbohydrates and as probes for cell surface receptors.